Two of the most important preventable risk factors for human morbidity and mortality are exposure to cigarette smoke and obesity, each raising the risk of cancer, cardiovascular, or respiratory disease. Oxidative stress may be the unifying mechanism underlying the development of co-morbidities of smoking and obesity and for the interaction of these risk factors with other environmental toxicants and the genome. Thus, this project will build upon our Laboratory's experience in sensor development, tobacco smoke inhalation toxicology, transcriptomics, and proteomics, to conduct controlled exposure studies in normal and obese mice to materials that produce inflammation and/or oxidative stress. Studies will be conducted with cigarette smoke (mainstream vs. sidestream) to complement the human studies described in Project 1, followed by exposures to the inflammatory bacterial agent, endotoxin (lipopolysaccharide, LPS), and the lung and liver oxidants, paraquat and carbon tetrachloride, to test mode-of-action and tissue-dependent responses. The mouse studies will facilitate discovery, verification, refinement and validation of candidate protein biomarkers of oxidative stress and inflammation using mass spectrometry proteomic approaches that will be added to PNNL's two proposed biosensor platforms-a laboratory-based sandwich ELISA microarray capable of quantitating dozens of protein biomarkers (Core B) and an in-clinic deployable nanoparticlebased, multiplexed immunochromatographic electrochemical biosensor capable of quantitating multiple biomarkers of exposure (e.g. an environmental chemical and/or its metabolites) and response (protein biomarkers of oxidative stress and inflammation) (Project 3). The mouse studies will enable comparisons of responses in target tissues, which cannot be done in humans, with biomarkers of oxidative stress/inflammation that can be quantitated in samples collected by progressively less invasive approaches (e.g. bronchoalveolar lavage fluid, plasma, saliva) to facilitate biosensor platform deployment in large scale human biomonitoring studies. Furthermore, this project provides parallel examination of the responses in normal mice with those in obese mice to identify key biological pathways that define the relationships between the environmental factors contributing to susceptibility, thereby creating an important database of global gene and protein profiling to perform mouse to human extrapolations.